aboutsummaryrefslogtreecommitdiff
path: root/src/mapgen/mapgen_v7.cpp
blob: 6b0779e9f2275fe7b48852fad1b7808c0deb5695 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
/*
Minetest
Copyright (C) 2014-2020 paramat
Copyright (C) 2013-2016 kwolekr, Ryan Kwolek <kwolekr@minetest.net>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/


#include "mapgen.h"
#include <cmath>
#include "voxel.h"
#include "noise.h"
#include "mapblock.h"
#include "mapnode.h"
#include "map.h"
#include "nodedef.h"
#include "voxelalgorithms.h"
//#include "profiler.h" // For TimeTaker
#include "settings.h" // For g_settings
#include "emerge.h"
#include "dungeongen.h"
#include "cavegen.h"
#include "mg_biome.h"
#include "mg_ore.h"
#include "mg_decoration.h"
#include "mapgen_v7.h"


FlagDesc flagdesc_mapgen_v7[] = {
	{"mountains",   MGV7_MOUNTAINS},
	{"ridges",      MGV7_RIDGES},
	{"floatlands",  MGV7_FLOATLANDS},
	{"caverns",     MGV7_CAVERNS},
	{NULL,          0}
};


////////////////////////////////////////////////////////////////////////////////


MapgenV7::MapgenV7(MapgenV7Params *params, EmergeParams *emerge)
	: MapgenBasic(MAPGEN_V7, params, emerge)
{
	spflags            = params->spflags;
	mount_zero_level   = params->mount_zero_level;
	floatland_ymin     = params->floatland_ymin;
	floatland_ymax     = params->floatland_ymax;
	floatland_taper    = params->floatland_taper;
	float_taper_exp    = params->float_taper_exp;
	floatland_density  = params->floatland_density;
	floatland_ywater   = params->floatland_ywater;

	cave_width         = params->cave_width;
	large_cave_depth   = params->large_cave_depth;
	small_cave_num_min = params->small_cave_num_min;
	small_cave_num_max = params->small_cave_num_max;
	large_cave_num_min = params->large_cave_num_min;
	large_cave_num_max = params->large_cave_num_max;
	large_cave_flooded = params->large_cave_flooded;
	cavern_limit       = params->cavern_limit;
	cavern_taper       = params->cavern_taper;
	cavern_threshold   = params->cavern_threshold;
	dungeon_ymin       = params->dungeon_ymin;
	dungeon_ymax       = params->dungeon_ymax;

	// Allocate floatland noise offset cache
	this->float_offset_cache = new float[csize.Y + 2];

	// 2D noise
	noise_terrain_base =
		new Noise(&params->np_terrain_base,    seed, csize.X, csize.Z);
	noise_terrain_alt =
		new Noise(&params->np_terrain_alt,     seed, csize.X, csize.Z);
	noise_terrain_persist =
		new Noise(&params->np_terrain_persist, seed, csize.X, csize.Z);
	noise_height_select =
		new Noise(&params->np_height_select,   seed, csize.X, csize.Z);
	noise_filler_depth =
		new Noise(&params->np_filler_depth,    seed, csize.X, csize.Z);

	if (spflags & MGV7_MOUNTAINS) {
		// 2D noise
		noise_mount_height =
			new Noise(&params->np_mount_height, seed, csize.X, csize.Z);
		// 3D noise, 1 up, 1 down overgeneration
		noise_mountain =
			new Noise(&params->np_mountain,     seed, csize.X, csize.Y + 2, csize.Z);
	}

	if (spflags & MGV7_RIDGES) {
		// 2D noise
		noise_ridge_uwater =
			new Noise(&params->np_ridge_uwater, seed, csize.X, csize.Z);
		// 3D noise, 1 up, 1 down overgeneration
		noise_ridge =
			new Noise(&params->np_ridge,        seed, csize.X, csize.Y + 2, csize.Z);
	}

	if (spflags & MGV7_FLOATLANDS) {
		// 3D noise, 1 up, 1 down overgeneration
		noise_floatland =
			new Noise(&params->np_floatland,    seed, csize.X, csize.Y + 2, csize.Z);
	}

	// 3D noise, 1 down overgeneration
	MapgenBasic::np_cave1    = params->np_cave1;
	MapgenBasic::np_cave2    = params->np_cave2;
	MapgenBasic::np_cavern   = params->np_cavern;
	// 3D noise
	MapgenBasic::np_dungeons = params->np_dungeons;
}


MapgenV7::~MapgenV7()
{
	delete noise_terrain_base;
	delete noise_terrain_alt;
	delete noise_terrain_persist;
	delete noise_height_select;
	delete noise_filler_depth;

	if (spflags & MGV7_MOUNTAINS) {
		delete noise_mount_height;
		delete noise_mountain;
	}

	if (spflags & MGV7_RIDGES) {
		delete noise_ridge_uwater;
		delete noise_ridge;
	}

	if (spflags & MGV7_FLOATLANDS) {
		delete noise_floatland;
	}

	delete []float_offset_cache;
}


MapgenV7Params::MapgenV7Params():
	np_terrain_base      (4.0,   70.0,  v3f(600,  600,  600),  82341, 5, 0.6,  2.0),
	np_terrain_alt       (4.0,   25.0,  v3f(600,  600,  600),  5934,  5, 0.6,  2.0),
	np_terrain_persist   (0.6,   0.1,   v3f(2000, 2000, 2000), 539,   3, 0.6,  2.0),
	np_height_select     (-8.0,  16.0,  v3f(500,  500,  500),  4213,  6, 0.7,  2.0),
	np_filler_depth      (0.0,   1.2,   v3f(150,  150,  150),  261,   3, 0.7,  2.0),
	np_mount_height      (256.0, 112.0, v3f(1000, 1000, 1000), 72449, 3, 0.6,  2.0),
	np_ridge_uwater      (0.0,   1.0,   v3f(1000, 1000, 1000), 85039, 5, 0.6,  2.0),
	np_mountain          (-0.6,  1.0,   v3f(250,  350,  250),  5333,  5, 0.63, 2.0),
	np_ridge             (0.0,   1.0,   v3f(100,  100,  100),  6467,  4, 0.75, 2.0),
	np_floatland         (0.0,   0.7,   v3f(384,  96,   384),  1009,  4, 0.75, 1.618),
	np_cavern            (0.0,   1.0,   v3f(384,  128,  384),  723,   5, 0.63, 2.0),
	np_cave1             (0.0,   12.0,  v3f(61,   61,   61),   52534, 3, 0.5,  2.0),
	np_cave2             (0.0,   12.0,  v3f(67,   67,   67),   10325, 3, 0.5,  2.0),
	np_dungeons          (0.9,   0.5,   v3f(500,  500,  500),  0,     2, 0.8,  2.0)
{
}


void MapgenV7Params::readParams(const Settings *settings)
{
	settings->getFlagStrNoEx("mgv7_spflags", spflags, flagdesc_mapgen_v7);
	settings->getS16NoEx("mgv7_mount_zero_level",       mount_zero_level);
	settings->getS16NoEx("mgv7_floatland_ymin",         floatland_ymin);
	settings->getS16NoEx("mgv7_floatland_ymax",         floatland_ymax);
	settings->getS16NoEx("mgv7_floatland_taper",        floatland_taper);
	settings->getFloatNoEx("mgv7_float_taper_exp",      float_taper_exp);
	settings->getFloatNoEx("mgv7_floatland_density",    floatland_density);
	settings->getS16NoEx("mgv7_floatland_ywater",       floatland_ywater);

	settings->getFloatNoEx("mgv7_cave_width",           cave_width);
	settings->getS16NoEx("mgv7_large_cave_depth",       large_cave_depth);
	settings->getU16NoEx("mgv7_small_cave_num_min",     small_cave_num_min);
	settings->getU16NoEx("mgv7_small_cave_num_max",     small_cave_num_max);
	settings->getU16NoEx("mgv7_large_cave_num_min",     large_cave_num_min);
	settings->getU16NoEx("mgv7_large_cave_num_max",     large_cave_num_max);
	settings->getFloatNoEx("mgv7_large_cave_flooded",   large_cave_flooded);
	settings->getS16NoEx("mgv7_cavern_limit",           cavern_limit);
	settings->getS16NoEx("mgv7_cavern_taper",           cavern_taper);
	settings->getFloatNoEx("mgv7_cavern_threshold",     cavern_threshold);
	settings->getS16NoEx("mgv7_dungeon_ymin",           dungeon_ymin);
	settings->getS16NoEx("mgv7_dungeon_ymax",           dungeon_ymax);

	settings->getNoiseParams("mgv7_np_terrain_base",    np_terrain_base);
	settings->getNoiseParams("mgv7_np_terrain_alt",     np_terrain_alt);
	settings->getNoiseParams("mgv7_np_terrain_persist", np_terrain_persist);
	settings->getNoiseParams("mgv7_np_height_select",   np_height_select);
	settings->getNoiseParams("mgv7_np_filler_depth",    np_filler_depth);
	settings->getNoiseParams("mgv7_np_mount_height",    np_mount_height);
	settings->getNoiseParams("mgv7_np_ridge_uwater",    np_ridge_uwater);
	settings->getNoiseParams("mgv7_np_mountain",        np_mountain);
	settings->getNoiseParams("mgv7_np_ridge",           np_ridge);
	settings->getNoiseParams("mgv7_np_floatland",       np_floatland);
	settings->getNoiseParams("mgv7_np_cavern",          np_cavern);
	settings->getNoiseParams("mgv7_np_cave1",           np_cave1);
	settings->getNoiseParams("mgv7_np_cave2",           np_cave2);
	settings->getNoiseParams("mgv7_np_dungeons",        np_dungeons);
}


void MapgenV7Params::writeParams(Settings *settings) const
{
	settings->setFlagStr("mgv7_spflags", spflags, flagdesc_mapgen_v7);
	settings->setS16("mgv7_mount_zero_level",           mount_zero_level);
	settings->setS16("mgv7_floatland_ymin",             floatland_ymin);
	settings->setS16("mgv7_floatland_ymax",             floatland_ymax);
	settings->setS16("mgv7_floatland_taper",            floatland_taper);
	settings->setFloat("mgv7_float_taper_exp",          float_taper_exp);
	settings->setFloat("mgv7_floatland_density",        floatland_density);
	settings->setS16("mgv7_floatland_ywater",           floatland_ywater);

	settings->setFloat("mgv7_cave_width",               cave_width);
	settings->setS16("mgv7_large_cave_depth",           large_cave_depth);
	settings->setU16("mgv7_small_cave_num_min",         small_cave_num_min);
	settings->setU16("mgv7_small_cave_num_max",         small_cave_num_max);
	settings->setU16("mgv7_large_cave_num_min",         large_cave_num_min);
	settings->setU16("mgv7_large_cave_num_max",         large_cave_num_max);
	settings->setFloat("mgv7_large_cave_flooded",       large_cave_flooded);
	settings->setS16("mgv7_cavern_limit",               cavern_limit);
	settings->setS16("mgv7_cavern_taper",               cavern_taper);
	settings->setFloat("mgv7_cavern_threshold",         cavern_threshold);
	settings->setS16("mgv7_dungeon_ymin",               dungeon_ymin);
	settings->setS16("mgv7_dungeon_ymax",               dungeon_ymax);

	settings->setNoiseParams("mgv7_np_terrain_base",    np_terrain_base);
	settings->setNoiseParams("mgv7_np_terrain_alt",     np_terrain_alt);
	settings->setNoiseParams("mgv7_np_terrain_persist", np_terrain_persist);
	settings->setNoiseParams("mgv7_np_height_select",   np_height_select);
	settings->setNoiseParams("mgv7_np_filler_depth",    np_filler_depth);
	settings->setNoiseParams("mgv7_np_mount_height",    np_mount_height);
	settings->setNoiseParams("mgv7_np_ridge_uwater",    np_ridge_uwater);
	settings->setNoiseParams("mgv7_np_mountain",        np_mountain);
	settings->setNoiseParams("mgv7_np_ridge",           np_ridge);
	settings->setNoiseParams("mgv7_np_floatland",       np_floatland);
	settings->setNoiseParams("mgv7_np_cavern",          np_cavern);
	settings->setNoiseParams("mgv7_np_cave1",           np_cave1);
	settings->setNoiseParams("mgv7_np_cave2",           np_cave2);
	settings->setNoiseParams("mgv7_np_dungeons",        np_dungeons);
}


void MapgenV7Params::setDefaultSettings(Settings *settings)
{
	settings->setDefault("mgv7_spflags", flagdesc_mapgen_v7,
		MGV7_MOUNTAINS | MGV7_RIDGES | MGV7_CAVERNS);
}


////////////////////////////////////////////////////////////////////////////////


int MapgenV7::getSpawnLevelAtPoint(v2s16 p)
{
	// If rivers are enabled, first check if in a river
	if (spflags & MGV7_RIDGES) {
		float width = 0.2f;
		float uwatern = NoisePerlin2D(&noise_ridge_uwater->np, p.X, p.Y, seed) *
			2.0f;
		if (std::fabs(uwatern) <= width)
			return MAX_MAP_GENERATION_LIMIT; // Unsuitable spawn point
	}

	// Terrain noise 'offset' is the average level of that terrain.
	// At least 50% of terrain will be below the higher of base and alt terrain
	// 'offset's.
	// Raising the maximum spawn level above 'water_level + 16' is necessary
	// for when terrain 'offset's are set much higher than water_level.
	s16 max_spawn_y = std::fmax(std::fmax(noise_terrain_alt->np.offset,
			noise_terrain_base->np.offset),
			water_level + 16);
	// Base terrain calculation
	s16 y = baseTerrainLevelAtPoint(p.X, p.Y);

	// If mountains are disabled, terrain level is base terrain level.
	// Avoids mid-air spawn where mountain terrain would have been.
	if (!(spflags & MGV7_MOUNTAINS)) {
		if (y < water_level || y > max_spawn_y)
			return MAX_MAP_GENERATION_LIMIT; // Unsuitable spawn point

		// y + 2 because y is surface level and due to biome 'dust'
		return y + 2;
	}

	// Search upwards for first node without mountain terrain
	int iters = 256;
	while (iters > 0 && y <= max_spawn_y) {
		if (!getMountainTerrainAtPoint(p.X, y + 1, p.Y)) {
			if (y <= water_level || y > max_spawn_y)
				return MAX_MAP_GENERATION_LIMIT; // Unsuitable spawn point

			// y + 1 due to biome 'dust'
			return y + 1;
		}
		y++;
		iters--;
	}

	// Unsuitable spawn point
	return MAX_MAP_GENERATION_LIMIT;
}


void MapgenV7::makeChunk(BlockMakeData *data)
{
	// Pre-conditions
	assert(data->vmanip);
	assert(data->nodedef);
	assert(data->blockpos_requested.X >= data->blockpos_min.X &&
		data->blockpos_requested.Y >= data->blockpos_min.Y &&
		data->blockpos_requested.Z >= data->blockpos_min.Z);
	assert(data->blockpos_requested.X <= data->blockpos_max.X &&
		data->blockpos_requested.Y <= data->blockpos_max.Y &&
		data->blockpos_requested.Z <= data->blockpos_max.Z);

	//TimeTaker t("makeChunk");

	this->generating = true;
	this->vm = data->vmanip;
	this->ndef = data->nodedef;

	v3s16 blockpos_min = data->blockpos_min;
	v3s16 blockpos_max = data->blockpos_max;
	node_min = blockpos_min * MAP_BLOCKSIZE;
	node_max = (blockpos_max + v3s16(1, 1, 1)) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
	full_node_min = (blockpos_min - 1) * MAP_BLOCKSIZE;
	full_node_max = (blockpos_max + 2) * MAP_BLOCKSIZE - v3s16(1, 1, 1);

	blockseed = getBlockSeed2(full_node_min, seed);

	// Generate base and mountain terrain
	s16 stone_surface_max_y = generateTerrain();

	// Create heightmap
	updateHeightmap(node_min, node_max);

	// Init biome generator, place biome-specific nodes, and build biomemap
	if (flags & MG_BIOMES) {
		biomegen->calcBiomeNoise(node_min);
		generateBiomes();
	}

	// Generate tunnels, caverns and large randomwalk caves
	if (flags & MG_CAVES) {
		// Generate tunnels first as caverns confuse them
		generateCavesNoiseIntersection(stone_surface_max_y);

		// Generate caverns
		bool near_cavern = false;
		if (spflags & MGV7_CAVERNS)
			near_cavern = generateCavernsNoise(stone_surface_max_y);

		// Generate large randomwalk caves
		if (near_cavern)
			// Disable large randomwalk caves in this mapchunk by setting
			// 'large cave depth' to world base. Avoids excessive liquid in
			// large caverns and floating blobs of overgenerated liquid.
			generateCavesRandomWalk(stone_surface_max_y,
				-MAX_MAP_GENERATION_LIMIT);
		else
			generateCavesRandomWalk(stone_surface_max_y, large_cave_depth);
	}

	// Generate the registered ores
	if (flags & MG_ORES)
		m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);

	// Generate dungeons
	if (flags & MG_DUNGEONS)
		generateDungeons(stone_surface_max_y);

	// Generate the registered decorations
	if (flags & MG_DECORATIONS)
		m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);

	// Sprinkle some dust on top after everything else was generated
	if (flags & MG_BIOMES)
		dustTopNodes();

	// Update liquids
	updateLiquid(&data->transforming_liquid, full_node_min, full_node_max);

	// Calculate lighting
	// Limit floatland shadows
	bool propagate_shadow = !((spflags & MGV7_FLOATLANDS) &&
		node_max.Y >= floatland_ymin - csize.Y * 2 && node_min.Y <= floatland_ymax);

	if (flags & MG_LIGHT)
		calcLighting(node_min - v3s16(0, 1, 0), node_max + v3s16(0, 1, 0),
			full_node_min, full_node_max, propagate_shadow);

	this->generating = false;

	//printf("makeChunk: %lums\n", t.stop());
}


////////////////////////////////////////////////////////////////////////////////


float MapgenV7::baseTerrainLevelAtPoint(s16 x, s16 z)
{
	float hselect = NoisePerlin2D(&noise_height_select->np, x, z, seed);
	hselect = rangelim(hselect, 0.0f, 1.0f);

	float persist = NoisePerlin2D(&noise_terrain_persist->np, x, z, seed);

	noise_terrain_base->np.persist = persist;
	float height_base = NoisePerlin2D(&noise_terrain_base->np, x, z, seed);

	noise_terrain_alt->np.persist = persist;
	float height_alt = NoisePerlin2D(&noise_terrain_alt->np, x, z, seed);

	if (height_alt > height_base)
		return height_alt;

	return (height_base * hselect) + (height_alt * (1.0f - hselect));
}


float MapgenV7::baseTerrainLevelFromMap(int index)
{
	float hselect = rangelim(noise_height_select->result[index], 0.0f, 1.0f);
	float height_base = noise_terrain_base->result[index];
	float height_alt = noise_terrain_alt->result[index];

	if (height_alt > height_base)
		return height_alt;

	return (height_base * hselect) + (height_alt * (1.0f - hselect));
}


bool MapgenV7::getMountainTerrainAtPoint(s16 x, s16 y, s16 z)
{
	float mnt_h_n =
		std::fmax(NoisePerlin2D(&noise_mount_height->np, x, z, seed), 1.0f);
	float density_gradient = -((float)(y - mount_zero_level) / mnt_h_n);
	float mnt_n = NoisePerlin3D(&noise_mountain->np, x, y, z, seed);

	return mnt_n + density_gradient >= 0.0f;
}


bool MapgenV7::getMountainTerrainFromMap(int idx_xyz, int idx_xz, s16 y)
{
	float mounthn = std::fmax(noise_mount_height->result[idx_xz], 1.0f);
	float density_gradient = -((float)(y - mount_zero_level) / mounthn);
	float mountn = noise_mountain->result[idx_xyz];

	return mountn + density_gradient >= 0.0f;
}


bool MapgenV7::getRiverChannelFromMap(int idx_xyz, int idx_xz, s16 y)
{
	// Maximum width of river channel. Creates the vertical canyon walls
	float width = 0.2f;
	float absuwatern = std::fabs(noise_ridge_uwater->result[idx_xz]) * 2.0f;
	if (absuwatern > width)
		return false;

	float altitude = y - water_level;
	float height_mod = (altitude + 17.0f) / 2.5f;
	float width_mod = width - absuwatern;
	float nridge = noise_ridge->result[idx_xyz] * std::fmax(altitude, 0.0f) / 7.0f;

	return nridge + width_mod * height_mod >= 0.6f;
}


bool MapgenV7::getFloatlandTerrainFromMap(int idx_xyz, float float_offset)
{
	return noise_floatland->result[idx_xyz] + floatland_density - float_offset >= 0.0f;
}


int MapgenV7::generateTerrain()
{
	MapNode n_air(CONTENT_AIR);
	MapNode n_stone(c_stone);
	MapNode n_water(c_water_source);

	//// Calculate noise for terrain generation
	noise_terrain_persist->perlinMap2D(node_min.X, node_min.Z);
	float *persistmap = noise_terrain_persist->result;

	noise_terrain_base->perlinMap2D(node_min.X, node_min.Z, persistmap);
	noise_terrain_alt->perlinMap2D(node_min.X, node_min.Z, persistmap);
	noise_height_select->perlinMap2D(node_min.X, node_min.Z);

	if (spflags & MGV7_MOUNTAINS) {
		noise_mount_height->perlinMap2D(node_min.X, node_min.Z);
		noise_mountain->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
	}

	//// Floatlands
	// 'Generate floatlands in this mapchunk' bool for
	// simplification of condition checks in y-loop.
	bool gen_floatlands = false;
	u8 cache_index = 0;
	// Y values where floatland tapering starts
	s16 float_taper_ymax = floatland_ymax - floatland_taper;
	s16 float_taper_ymin = floatland_ymin + floatland_taper;

	if ((spflags & MGV7_FLOATLANDS) &&
			node_max.Y >= floatland_ymin && node_min.Y <= floatland_ymax) {
		gen_floatlands = true;
		// Calculate noise for floatland generation
		noise_floatland->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);

		// Cache floatland noise offset values, for floatland tapering
		for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++, cache_index++) {
			float float_offset = 0.0f;
			if (y > float_taper_ymax) {
				float_offset = std::pow((y - float_taper_ymax) / (float)floatland_taper,
					float_taper_exp) * 4.0f;
			} else if (y < float_taper_ymin) {
				float_offset = std::pow((float_taper_ymin - y) / (float)floatland_taper,
					float_taper_exp) * 4.0f;
			}
			float_offset_cache[cache_index] = float_offset;
		}
	}

	// 'Generate rivers in this mapchunk' bool for
	// simplification of condition checks in y-loop.
	bool gen_rivers = (spflags & MGV7_RIDGES) && node_max.Y >= water_level - 16 &&
		!gen_floatlands;
	if (gen_rivers) {
		noise_ridge->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
		noise_ridge_uwater->perlinMap2D(node_min.X, node_min.Z);
	}

	//// Place nodes
	const v3s16 &em = vm->m_area.getExtent();
	s16 stone_surface_max_y = -MAX_MAP_GENERATION_LIMIT;
	u32 index2d = 0;

	for (s16 z = node_min.Z; z <= node_max.Z; z++)
	for (s16 x = node_min.X; x <= node_max.X; x++, index2d++) {
		s16 surface_y = baseTerrainLevelFromMap(index2d);
		if (surface_y > stone_surface_max_y)
			stone_surface_max_y = surface_y;

		cache_index = 0;
		u32 vi = vm->m_area.index(x, node_min.Y - 1, z);
		u32 index3d = (z - node_min.Z) * zstride_1u1d + (x - node_min.X);

		for (s16 y = node_min.Y - 1; y <= node_max.Y + 1;
				y++,
				index3d += ystride,
				VoxelArea::add_y(em, vi, 1),
				cache_index++) {
			if (vm->m_data[vi].getContent() != CONTENT_IGNORE)
				continue;

			bool is_river_channel = gen_rivers &&
				getRiverChannelFromMap(index3d, index2d, y);
			if (y <= surface_y && !is_river_channel) {
				vm->m_data[vi] = n_stone; // Base terrain
			} else if ((spflags & MGV7_MOUNTAINS) &&
					getMountainTerrainFromMap(index3d, index2d, y) &&
					!is_river_channel) {
				vm->m_data[vi] = n_stone; // Mountain terrain
				if (y > stone_surface_max_y)
					stone_surface_max_y = y;
			} else if (gen_floatlands &&
					getFloatlandTerrainFromMap(index3d,
					float_offset_cache[cache_index])) {
				vm->m_data[vi] = n_stone; // Floatland terrain
				if (y > stone_surface_max_y)
					stone_surface_max_y = y;
			} else if (y <= water_level) { // Surface water
				vm->m_data[vi] = n_water;
			} else if (gen_floatlands && y >= float_taper_ymax && y <= floatland_ywater) {
				vm->m_data[vi] = n_water; // Water for solid floatland layer only
			} else {
				vm->m_data[vi] = n_air; // Air
			}
		}
	}

	return stone_surface_max_y;
}